Recurrence of coronavirus is “almost inevitable” once restrictions end, until enough people build up immunity through vaccination or surviving infection, a senior official in Northern Ireland has said.

Up to 3,000 people could die during a first wave, expected to peak in around a fortnight, the chief scientific officer advising the Stormont government said.

No decision has yet been made about when to ease measures largely confining people to home except for work, essential shopping and exercise.Professor Ian Young advises the Stormont Health Department (Kelvin Boyes/PA)

Professor Ian Young warned: “Once you relax restrictions it is almost inevitable that there will be a recurrence of the virus and that will occur until a substantial proportion of the population have immunity.”

Immunity is built up through having had the infection or receiving a vaccine, which is still in development.

The professor advises the Stormont Health Department, which is helping coordinate the fight against Covid-19.

The first wave could last into late summer.

He said no decisions had been made about when social distancing recommendations would be relaxed.

“We will be looking carefully at the likely impact of relaxing those recommendations, either singly or as a group,” he said.(PA Graphics)

Today, the North's Public Health Agency said there had been two deaths of people who tested positive for Covid-19 since the last update on Tuesday, bringing the total to 30.

Most positive cases are in Belfast (200), followed by Lisburn (81), and the Armagh, Banbridge and Craigavon council area (70). The fewest are in the Causeway Coast and Glens council area (18).

The modelled reasonable worst case scenario is based on social distancing measures producing a 66% reduction in contacts outside the home and workplace. In addition, 70% of symptomatic people would self-isolate.

First Minister Arlene Foster said the toll would be about 500 short of that inflicted by 30 years of violence in Northern Ireland.

She added: “The loss of each of those lives is a huge blow, not only to their families, but of course to the communities from which they come from.

“In a small tight-knit society like ours, we are all likely to know someone who will be impacted, and it will be a cruel blow and we will need to do everything we can to comfort and support their relatives, and indeed each other, in the difficult weeks and months ahead.”

Deputy First Minister Michelle O’Neill said the modelling was alarming.

“People will be concerned, it’s a scary prospect for all of us but particularly for those older people and people who are vulnerable,” she said.

Mrs Foster “stood firmly behind” advice from Northern Ireland’s chief medical officer Michael McBride on testing, but said the ministerial Executive was united in wanting to do everything it could to halt the disease’s spread.

Mrs O’Neill said Northern Ireland should be following World Health Organisation advice more closely.